Developing my own Class (or Package?)

I am very new to Java.
I would like to write a Class (or Package) that I can give to software developers so that they can call my routines (it is quite small).
I decided to try it on a Hello World program, which has a helloworld package.
It only seems to work properly if I make the class part of the helloworld package. i.e. have "package helloworld" as my first line.
However, I want my class to be independent of the helloworld package. But, if I do that I cannot access it from helloworld.
How do I do this?
Or should I be writing a package? How do I do this?

The package line tells the JVM where to look for the class file, and should have the same name as the directory in which it is located, under your classpath. If you want to be able to access the class without using the package, you will have to move the class file up one directory so that it sits directly in your classpath.
Steve

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How do i put classes in package in NetBean Environment

Hello,
I install NetBean IDE for developing website using JSP and Servlet. I am using Internal Tomcat provided by this IDE.
Problem is this i put java classes in the Class folder of Web-INF folder, but i am not able to access these classes from JSp page.
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hai
i have the same problem to finding the classes in package...
in my case i know the jars name and i have loaded
classes using code
ResourceBundle bundle = ResourceBundle.getBundle("source\\ClasssPath");
StringTokenizer stToke = new StringTokenizer(bundle.getString("ClassPath"),";");
String temp;
ClassLoader classLoader = ClassLoader.getSystemClassLoader();
while(stToke.hasMoreTokens())
     temp = stToke.nextToken().trim();
if(temp.endsWith(".jar"))
JarFile jar = new JarFile(new File(temp));
     Enumeration en = jar.entries();
     String pathStr;
     while(en.hasMoreElements())
     pathStr = en.nextElement().toString();
     System.out.println("pathStr ="+pathStr);
     if(pathStr.endsWith(".class"))
          System.out.println( classLoader.getResource(pathStr));
          System.out.println(classLoader.loadClass(pathStr.substring(0,pathStr.indexOf(".class")).replace('/','.').trim()));
     else classLoader.loadClass(temp);
here i am getting the classes in that package using code
     String[] filLis = new File("//it//sella//converter//ptlf//startup//").list();
     int length = filLis.length;
     while(length-- >0)
     System.out.println(">"+filLis[length]);
but its returnign the class when this classes in locale folder(i.e)its not getting the classes in loaded memory...
so how to retrieve the class files names using package structure name...
(i am having more then 20 jars files, inthat inside the jar samepackage structue may appear in more then one jars )
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Thanx

HELP: Import my own class in JSP ???

Hi, all!
I read many previous topics in this forum but no one works for me!
Please someone help me!
I'm using Tomcat 4.1.12 and my JSP scripts work just fine, but I need to import my own .class file. I just don't know where to put it so Tomcat can find it!?
I have this environment variable:
JAVA_HOME=.;c:\jdk1.3.1
And in my code I'want to place something like this:
<%@ page import="myClass" %>
But I get a "can not resolve symbol" exception.
Thanks for readind this, and please help if you can!
Bye.
adriano

Within the Tomcat directory, under your application directory place the class file/s into the WEB-INF/classes directory. If your classes are part of a package place the entire directory structure of the package under the WEB-INF/classes directory.
The import in the JSP is the same as for any Java class.
Hope this solves your problem.

How can I import my class or package in JSP?

Hello.
I develop jsp. When I assign variables in jsp, everything work fine. For Example:
connStr="jdbc:oracle:thin:@191.168.0.1:1521:orcl";
But I want put some variables inside class or package, so using text editor I created and compiled package:
package Pack1;
public class Test1 extends java.lang.Object {
public static void main(String[] args) {
String ConnStr = "jdbc:oracle:thin:@191.168.0.1:1521:orcl";
or class
class Test1 {
public static void main(String[] args) {
String connStr = "jdbc:oracle:thin:@191.168.0.1:1521:orcl";
But as soon as I put in my jsp line
<%@ page import="Test1" %> or <%@ page import="Pack1.*" %>
I always have an error.
JSP Error:
Request URI:/DateN/search/Search.jsp
Exception:
oracle.jsp.provider.JspCompileException:
Errors compiling:e:\orant\oem8i\apache\apache\htdocs\daten\_pages\_daten\_search\_Search.java
C:\orant\oem8i\apache\apache\htdocs\daten\_pages\_daten\_search\_Search.java:12: Package DateN not found in import.
import Pack1.*; (or Test1)
^
1 error
I using OEM2.2 with Apache-Server under Win2000. I put my classes:
Test1 in package: in folder: C:\orant\oem8i\Apache\Apache\htdocs\WEB-INF\classes\Pack1
If just class, when just in folder: C:\orant\oem8i\Apache\Apache\htdocs\WEB-INF\classes
If I using just class, when I put just in folder: C:\orant\oem8i\Apache\Apache\htdocs\WEB-INF\classes.
Im stack. Anybody can help?
Thank you.

Another way. You can use a USB flash drive & the camera connection kit.
Plug the USB flash drive into your computer & create a new folder titled DCIM. Then put your movie/photo files into the folder. The files must have a filename with exactly 8 characters long (no spaces) plus the file extension (i.e., my-movie.mov; DSCN0164.jpg).
Now plug the flash drive into the iPad using the camera connection kit. Open the Photos app, the movie/photo files should appear & you can import. (You can not export using the camera connection kit.)
Secrets of the iPad Camera Connection Kit
http://howto.cnet.com/8301-11310_39-57401068-285/secrets-of-the-ipad-camera-conn ection-kit/
 Cheers, Tom

No intelli sense on my own classes

I don't get a drag-down intelli-sense menue when i
type the name of one of my own classes and press ctrl+space.
Anyone who has had the simular problem, and know the answer?
The classes are all in the same package.

Through the tools menue for the folder and "update parser database..."?
In that case I have to do it for each folder/project?
I'd like to have it done automaticly. On some other
computers I have programmed on, the drop-down-menu
appears without me updating the parser database.
Has it something to do with the setup?

Problem with creating my own class...

Hi all,
Purpose with this program:
I want to create my own class StringThing which take a string parameter and transform the content toUpperCase().
I have created a simple class StringThing which look like this:
class StringThing {
public String upperize (String u) {
u.toUpperCase();
return u;
}And my class where I use the StringThing looks like this:
import java.io.*;
class UseStringThing{
public static void main (String arg[]) throws Exception {
BufferedReader keyboard = new BufferedReader(
new InputStreamReader(System.in));
String s,p;
System.out.prinln("write a sentence!");
s=keyboard.readLine();
StringThing thing = new StringThing();
p=thing.upperize(s);
System.out.println(p);
}Am I not supposed to transform my string parameter in my class by using for instance toUpperCase()? Or is there some fundamental rule or piece of code which I forgot?
Thanks in advance,
/Beginner-T-who-ripps-his-hear-over-this-small-problem

Strings cannot be modified. What this line does:
u.toUpperCase();
is to create a new String object. toUpperCase() returns the newly created string and you are ignoring the returned value. What you want to do is:
return u.toUpperCase();
or
u = u.toUpperCase();

How can I turn off the WLS 6.1 security in order to develop my own application-based security module?

Dear Colleagues,
I am currently developing a J2EE application using WLS 6.1.
My team and I have to implement a security requirement to suit our company's needs.
The security requirements are that, users' password need to be aged (30 days maximum) and we need to provided a GUI front-end (JSP) to allow users to change their password when these expire after 30 days.
Our internal contacts in the company, have already taken the lead to find out about whether we will be able to use the WLS 6.1 platform to do this and the answer we got back, was.
Now we need to develop our own security module.
I have 2 questions:
1. How can we turn off the WLS security in order develop our own application-based security module?
2. How can we develop a security module that allows us to age users' password and provide them with facilities to change their passwords when these expire?
At the moment, we are using the default BEA WebLogic login.jsp page and there some configuration in the web.xml for this. I will be grateful if you could advise me on how to turn this default security off so that we can write our own security module.

hi,
1.You can write your own realm in 61 which can plugged for your security
calls.
2. once you write your ownrealm.. you can access it through weblogic
api/ur api..
thanks
kiran
"Richard Koudry" <[email protected]> wrote in message
news:3dd0d081$[email protected]..
Dear Colleagues,
I am currently developing a J2EE application using WLS 6.1.
My team and I have to implement a security requirement to suit ourcompany's needs.
>
The security requirements are that, users' password need to be aged (30days maximum) and we need to provided a GUI front-end (JSP) to allow users
to change their password when these expire after 30 days.
>
Our internal contacts in the company, have already taken the lead to findout about whether we will be able to use the WLS 6.1 platform to do this and
the answer we got back, was.
>
Now we need to develop our own security module.
I have 2 questions:
1. How can we turn off the WLS security in order develop our ownapplication-based security module?
>
2. How can we develop a security module that allows us to age users'password and provide them with facilities to change their passwords when
these expire?
>
At the moment, we are using the default BEA WebLogic login.jsp page andthere some configuration in the web.xml for this. I will be grateful if you
could advise me on how to turn this default security off so that we can
write our own security module.

How can I create a new own class in WebDynpro?

I test the Web Dynpro for a while and found all the java classes were generated automatically. I've tried to create an own class. But after I rebuild the project, all of my own classes were cleared.

Hi
You can create your own class as mentioned in above replies or one more way,
1. first you create your java project seperately, there you can write all your business needs and then, make a jar or that then, you can include that project into your WDproject by
rightclick on WDproject>properties>libraries>addexternaljars>ok
2. create seperate java project
rightclick on WDproject>properties>Projects>selectYourjavaProject>ok
Regards
Abhijith YS

Not allowed to import classes without package names?

Hi,
I have a few questions on Packages and importing?
1. Is the following true that it is illegal to import classes in the same package as the current class, will this cause a comilation error? If this is the case where in the Java Language specification is this actually written as I could not find it?
2. This has probably been answered by question 1 but if I have 2 classes in the same package and if I import 1 of the classes into the other class, is it illegal to import it by just using the class name and not the package name as well, ie
if the package name is ie.tcd
and the 2 class names are exp1.class and exp2.class, can I do this in class 2
package ie.tcd;
import exp1;
public class exp2 {
3. Is it illegal to import classes that are not explicitly part of any package or must a class be part of a package to be imported. I read somewhere that while this was always illegal it is only after jdk 1.4.2 that this is being enforced? If this is the case where in the Java Language specification is this actually written as I could not find it either?
Thanks very much for any help,
John

Was just also wondering, 1 other thing, I am looking
at someone elses code they have 2 classes (Class A
and Class B) in the same package (pkg). The person
imports class A into B:
package pkg;
import A;
public class B {
Is this legal code (or was it ever)?Not if A is really in pkg.A. If there is an A in the unnamed package it was legal, or at least it was understood by the compiler, and now it isn't (to both).
Can you import or is there a point in importing a class in the same
package?Only by naming the package in the import statement. If the current and the import statement are in the same package the import is redundant.
If there is a point would you import just be
using the class name (this would be illegal after jdk
1.4) or should you use the whole package name even
though it is in the package anyways?As I understand it you must always use the whole package name in imports.

How to get context information in your own class

Hi,
I'm new to Java and I'm trying to create my own class which stores some constants like for example mailServerHost. The class would look something like this:
public class AppSettings {
private static String mailServerHost="localhost";
static{
if(###online-server###)
mailServerHost="another mail server";
My problem is the if(###online-server###). I don't know how could I find informations about the underlying server.
Is there any way to find out informations about the context(server)?
Thanks,
IMIA

Do you still need ?n this case 2 different
property-files (one for dev and one for
online-servers).Yes, but they would have the same name. ;-)
After all when you need to load one
of them you'd still need in your AppSettings class on
which server your application is running. So I'd
still need that information.No, you use a fixed name, e.g. server.properties, for the config file.
You might find class java.util.ResourceBundle interesting.

Import my own class into servlet problem

Hello, everyone.. I fail to import java classes that i create myself into the servlet. I wonder what is the problem. I would feel grateful if anyone can solve my problem. I noe that if it is in the package let say myclass , C:\jakarta-tomcat-4.1.29\webapps\lis\WEB-INF\classes\myclass. It will be
package myclass;
import myclass.*;
But, I put all my class file into below directory not in a package.
C:\jakarta-tomcat-4.1.29\webapps\lis\WEB-INF\classes
and i wish to include let say DBManager.class file into Login.class file which in in the same directory as above. What is the correct code i should put? Thanks for anyone who willing to help me out ~

You don't need to import classes from the same package. They are automatically available in the same namespace. Just use them.
package myclasses;
import myclasses.*; // this line does nothing
import myctherclasses.*; // this line is necessary to use classes from another package.Having said that though, it is always preferable to put your classes in a package. Classes in the "unnamed" package are not guarunteed to be available anymore.
Particularly servlet classes which are not in a package aren't found by Tomcat.
In short: always put your classes into packages.
Cheers,
evnafets

Classes without packages not accepted by ejbc compilation ?

Hey guys ...
I noticed something which I found unusual...I mite be missing something out here
When ejbc generates the Bean IMPL class , it does not put any import statements
in the generated java file but references all the classes in the Bean with their
absolute path ...
Now ..I have a 3rd-party jar which does not have certain classes in packages...and
I reference these classes within my Session Bean...the session bean compiles properly
..but when ejbc happens and the Impl class gets generated with the absolute path
and no imports...the compiler expects to find all these 3rd-party classes without
packages within the current session bean package itself which it will not..and
hence throws all sorts of "cannot resolve symbol" errors...
Does this mean that within my EJB beans I can never reference classes without
packages or is there something I am missing..?
Thanx,
Krish

Rob ,
I agree with u that giving classes without package is not a good practise..but
Itz got a history which believe it or not stems from another weblogic problem(related
to webservices..)
anywayz..that is another issue alltogether...
I don't think this bug is fixed...coz I checked a WLS70 Impl and it is still generating
the IMPL without the imports...
But can u clarify..what u wud mean by "fixing the bug" ..does it mean that the
Impl would start putting the imports..?
Thanx,
Krish
Rob Woollen <[email protected]> wrote:
I recall this bug being reported before. You might try the latest
service pack and see if it's been fixed already. Otherwise, you'll have
to contact [email protected]
FWIW, it's quite disturbing that a 3rd party would give you a jar
without a package.
-- Rob
Krishnan Venkataraman wrote:
Hey guys ...
I noticed something which I found unusual...I mite be missing
something out here
When ejbc generates the Bean IMPL class , it does not put any import
statements
in the generated java file but references all the classes in the Bean
with their
absolute path ...
Now ..I have a 3rd-party jar which does not have certain classes in
packages...and
I reference these classes within my Session Bean...the session bean
compiles properly
..but when ejbc happens and the Impl class gets generated with the
absolute path
and no imports...the compiler expects to find all these 3rd-party
classes without
packages within the current session bean package itself which it will
not..and
hence throws all sorts of "cannot resolve symbol" errors...
Does this mean that within my EJB beans I can never reference classes
without
packages or is there something I am missing..?
Thanx,
Krish

Import class without package

hellow, i have a web aplication named test , and i have a class named conexion
when i import a package "pack" with the class conexion, not problem (test/WEB-INF/classes/pack/conexion.class) <% import="pack.* " %> but when i have only the class conexion WITHOUT package (test/WEB-INF/classes/conexion.class) and i import <%import ="conexion" %> i have problem ("The import conexion cannot be resolved") and when i not import the class i have problem (conexion cannot be resolved to a type) , my question is:
how to i import a class without package in JSP , and if the test/WEB-INF/classes is in the classpath when compile the servlet , why the tomcat not found the class conexion?
(tomcat 5.5.20 , jdk 1.5.09 , vim)
thank
(Sorry my english , i'm from Chile)

Hi I am hosting my JSP application with Resin 2.17 which uses classes directly in JSP code (not packages). To make this work I had to specify the classpath in Resin.conf and it worked.
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How to create an object of our own class by using Class.forName()??

how to create an object of our own class by using Class.forName()??
plzz anser my qustion soon..

Class.forName does not create an object. It returns a reference to the Class object that describes the metadata for the class in question--what methods and fields it has, etc.
To create an object--regardless of whether it's your class or some other class--you could call newInstance on the Class object returned from Class.forName, BUT only if that class has a no-arg constructor that you want to call.
Class<MyClass> clazz = Class.forName("com.mycompany.MyClass");
MyClass mine = clazz.newInstance();If you want to use a constructor that takes parameters, you'll have to use java.lang.reflect.Constructor.
Google for java reflection tutorial for more details.
BUT reflection is often abused, and often employe when not needed. Why is it that you think you need this?

Developing my own Class (or Package?)

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